Windmills have long been used for generating electricity. Conventional windmills generally take the form of a wind turbine having a plurality of blades or surfaces which are connected to a central shaft by lever arms. The blades serve to catch the wind such that the impingement of the wind upon the blades causes the central shaft to be rotated. By connecting the rotating shaft to a generator, the kinematic energy of the wind is converted to electricity. The angular velocity of such wind turbines are limited by the velocity of the wind.
In contrast to a wind turbine which relies upon the impact of the fluid particles upon the blade surfaces, a wind rotor utilizes aerodynamics resulting from the interaction of the fluid particles with airfoil-shaped blades. As the air particles move with respect to the blades, lifting forces are exerted on the blade. The wind rotor blades are connected to a central shaft by lever arms such that the lift generated on the blade by the moving fluid particles rotates the blades and the central shaft to produce electricity. While the angular velocity of the blades of the wind rotor are not limited by the wind velocity, the torque on the central shaft is limited by the component of the total lift forces which can be transmitted to the central shaft through the lever arms.
Total lift, which is perpendicular to the chord line of the airfoil blade, can be resolved into components which are parallel and non-parallel to the lever arm connecting the blade to the central shaft. In prior art wind rotors, the lever arm is straight and the blade is connected such that the chord line thereof is substantially perpendicular to the lever arm. Thus, in conventional wind rotors, the majority of the total lift acts in a line parallel to the lever arm and generates no torque upon the central shaft. Only a small component of the total lift is utilized in applying torque to the central shaft.
Therefore, a primary objective of the present invention is an improved wind rotor which produces greater torque upon the central shaft and therefore increases the amount of kinematic wind energy that can be converted to dynamic energy.
A further objective of the present invention is the provision of a wind rotor having airfoil blades connected to bent lever arms so as to utilize a greater portion of the total lift produced on the blades by the wind for increased torque upon the central shaft of the rotor.
Another objective of the present invention is the provision of a wind rotor wherein the angle of attack of the blades is selectively adjustable.
A still further objective of the present invention is the provision of a wind rotor which can be selectively rotated in either a clockwise or counter-clockwise direction.
A further objective of the present invention is the provision of a wind rotor which is self-starting.
Another objective of the present invention is the provision of a wind rotor having detachable blades.
Another objective of the present invention is the provision of a wind rotor which is economical to manufacture, and durable and efficient in use.